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Old 20-01-2013, 01:48 PM
garymck (Gary)
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garymck is offline
 
Join Date: Aug 2005
Location: Geelong
Posts: 822
Quote:
Originally Posted by allan gould View Post
I had a VC200L and found that a laser collimator was no good really due to the optics in the draw tube. I don't know how many had the scope before me but I suspect quite a few as when the secondary was inspected there were various different alignment marks all around it. I then used the written method by Vixen to do the whole thing by eye. Followed it exactly and my collimation was then quite good but still slightly triangular stars. I then used Al's collimation aid on a bright star to do the final collimation.
Result: Perfectly round stars to the edge native or with the focal reducer. But like an idiot sold it which I regret to this day and may get another.
Hi Allan,

Exactly how I felt about the original vc200l I had.

That one, I originally collimated with a Takahashi collimation scope (after centre spotting the secondary). Because that was borrowed, a friend made up the fitting to screw the laser to the focuser so there was no slop at all. i actually have to heat the fitting up to get the laser in to it! The laser and the tak scope were exactly in agreement about how the secondary was collimated...so in that scope the internal optics had no effect on the lasers ability to achieve secondary collimation accurately. The same can be said of my current vc200l it all matches. The hardest thing about the primary is learning that adjustment moves are TINY. It is incredibly easy to overshoot and end up chasing your tail...

Cheers
Gary
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